Cloning and analysis of cyclophilin-RNA interacting protein gene of Cryptosporidium parvum

Objective To obtain nucleotide sequences of cyclophilin-RNA interacting protein(CRIP) of Crygptosporidium parvum(C.parvum) Nanjing(NJ) strain by cloning and to analyze the difference in CRIP gene sequence between NJ strain and other strains.Methods According to known CRIP C.parvum gene sequences in GenBank,we designed and synthesized two pairs of primers to amplify the CRIP genes from the C.parvum NJ strain by nested PCR technique and cloned it into the pMD18-T vectors.Then the recombinant plasmids were sequenced by PCR and double enzyme digest method.We used bioinformatics methods to find out the homologies of the CRIP gene between C.parvum NJ strain and other strains.Results CRIP specific gene sequences were amplified by nested PCR and the correct recombinant plasmids were identified by PCR and double enzyme digest method.The results of nucleotide sequencing showed that the amplified sequence was 1 119 bp and the CRIP gene of the C.parvum NJ strain was 909 bp encoding 302 amino acids.The sequence analysis showed that there was a 98% homology in amino acids between NJ strain and the Iowa II strain abroad.Conclusion The CRIP gene of C.parvum NJ strain was cloned successfully.